Have you ever heard of the "The Wall drill"?
www.youtube.com/watch?v=r7YdjrvB718
Sorry, one of these days I need to understand how to post videos. They never work for me.
Here's a description from pistol training.com
Wall Drill
developed by George Harris, SIGARMS Academy
Range: 0yd
Target: blank wall
Start position: any
Rounds fired: 0 (dry fire)
This is a dry-fire drill; all weapons must be completely unloaded and double-checked before the start of this drill.
Shooter stands with muzzle at eye level less than one inch from a blank wall. There should be no aiming points (targets, holes, light switches, etc.) to distract the shooter.
Shooter practices proper sight alignment, front sight focus, and trigger manipulation without the distraction of a target. Two-handed, strong-hand, and weak-hand shooting should be practiced. For TDA (traditional double action) pistols, both the double- and single-action trigger pulls should be practiced.
The goal is to maintain focus on the front sight, pulling the trigger without upsetting sight alignment.